1. Field of the Invention
The present invention relates to an electrical connector for mounting on a printed circuit board, and particularly to an electrical connector with a grounding shell.
2. Description of Related Art
Electrical connectors are widely used in computers to transmit electrical signals. When the connectors are used in high-speed data transmission applications, the problem of electromagnetic interference (EMI) increases. A metal shell is used to enclose an insulating housing of the electrical connector for preventing outside EMI from affecting the signals transmitting through the connector, and to prevent EMI generated from within the connector from influencing outside circuits. The metal shell is generally stamped from a metal blank and is in a rectangular, box-like form. Side edges of the metal shell are engaged with each other by dovetail-shaped protrusions formed on the metal shell engaging in dovetail-shaped recesses defined in the metal shell. In practice, an engaging force between the side edges of the metal shell is not large enough and the side edges are easily disengaged from each other. Furthermore, after the metal shell is assembled on the housing, a gap exists between the metal shell and the housing and the gap is difficult to eliminate. When plugging or unpulling the connector from a mating connector, the mating connector may be damaged by the side edges of the metal shell. It is also relatively complex to assemble the metal shell, which increases the cost of the connector.
Hence, it is desirable to provide an electrical connector with an improved metal shell to overcome the above-mentioned disadvantages.
Accordingly, one object of the present invention is to provide an electrical connector with a metal shell enclosing an insulating housing thereof to provide shielding against electromagnetic interference.
Another object of the present invention is to provide an electrical connector with a spacer pressing against a metal shell, to prevent the shell from separating from the insulating housing.
In order to achieve the above-mentioned objects, an electrical connector comprises an insulating housing, a plurality of contacts, a metal shell and a spacer. The housing has opposite upper and lower walls and defines a mating cavity therebetween. A plurality of passageways are defined in the upper and lower walls and in communication with the mating cavity, a pair of protrusions extend downwardly from the lower wall. Each contact comprises a mating portion received in the passageway. The shell is stamped from a metal sheet and encloses the insulating housing. The shell comprises upper and lower body portions. The lower body portion includes a pair of end junction portions. Each end junction portion defines a receiving aperture for receiving a corresponding protrusion therein. The spacer has a base plate defining a plurality of through holes to allow extension of the contacts therethrough. The spacer is assembled to the housing and presses the lower body portion of the shell against the lower wall of the housing, holding the shell in firm retention against the housing.
Other objects, advantages and novel features of the invention will become more apparent from the following detailed description when taken in conjunction with the accompanying drawings.